U.S. patent application number 12/192017 was filed with the patent office on 2010-02-18 for array structure of nano materials.
This patent application is currently assigned to SEOUL NATIONAL UNIVERSITY RESEARCH & DEVELOPMENT BUSINESS FOUNDATION (SNU R&DB FOUNDATION). Invention is credited to Youngtack Shim.
Application Number | 20100040831 12/192017 |
Document ID | / |
Family ID | 41681448 |
Filed Date | 2010-02-18 |
United States Patent
Application |
20100040831 |
Kind Code |
A1 |
Shim; Youngtack |
February 18, 2010 |
ARRAY STRUCTURE OF NANO MATERIALS
Abstract
There is provided a novel array structure of nano materials. The
array structure may comprise a first set of conductive electrodes,
a second set of conductive electrodes and a plurality of first nano
material strands protruding from the first conductive electrodes.
The first nano material strands may be arranged in a coplanar
relationship on a first plane. The array structure may further
comprise a plurality of second nano material strands protruding
from the second conductive electrodes. The second nano material
strands may be arranged in a coplanar relationship on a second
plane, which is substantially parallel with the first plane. At
least a part of the second nano material strands may extend in a
transverse relationship with respect to at least a part of the
first nano material strands.
Inventors: |
Shim; Youngtack; (Seoul,
KR) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET, FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Assignee: |
SEOUL NATIONAL UNIVERSITY RESEARCH
& DEVELOPMENT BUSINESS FOUNDATION (SNU R&DB
FOUNDATION)
Seoul
KR
|
Family ID: |
41681448 |
Appl. No.: |
12/192017 |
Filed: |
August 14, 2008 |
Current U.S.
Class: |
428/141 ;
216/18 |
Current CPC
Class: |
G11C 13/0023 20130101;
G11C 11/52 20130101; B82Y 10/00 20130101; G11C 11/54 20130101; Y10T
428/24355 20150115; G11C 11/14 20130101; G11C 13/025 20130101; G11C
2213/81 20130101 |
Class at
Publication: |
428/141 ;
216/18 |
International
Class: |
B32B 5/02 20060101
B32B005/02; B44C 1/22 20060101 B44C001/22 |
Claims
1. An array structure of nano materials, comprising: a substrate; a
first set of conductive electrodes disposed on the substrate; a
second set of conductive electrodes disposed on the substrate; a
plurality of first nano material strands protruding from the first
conductive electrodes along at least a substantially similar first
direction and in a first elevation from the substrate; and a
plurality of second nano material strands protruding from the
second conductive electrodes along at least a substantially similar
second direction and in a second elevation from the substrate,
wherein the second elevation differs from the first elevation by at
most several hundreds of nanometers, wherein the first and second
nano materials are configured to interact with each other when
disposed adjacent to a target.
2. The array structure of nano materials of claim 1, wherein at
least parts of the first and second nano materials cross each other
in different elevations in any one of an acute angle, a right angle
and an obtuse angle.
3. The array structure of nano materials of claim 1, wherein at
least parts of the first and second nano materials extend in a
coplanar relationship.
4. The array structure of nano materials of claim 3, wherein the
coplanar relationship includes at least one of a direction of at
least one of the nano materials, a length of at least one of the
nano materials protruding from the electrodes and an arrangement
between at least two of the nano materials.
5. A array structure of nano materials, comprising: a first set of
conductive electrodes; a second set of conductive electrodes; a
plurality of first nano material strands protruding from the first
conductive electrodes, wherein the first nano material strands are
disposed in a coplanar relationship on a first plane; and a
plurality of second nano material strands protruding from the
second conductive electrodes, wherein the second nano material
strands are disposed in a coplanar relationship on a second plane
substantially parallel with the first plane, wherein at least a
part of the second nano material strands extends in a transverse
relationship with respect to at least a part of the first nano
material strands.
6. The array structure of nano materials of claim 5, wherein the
first conductive electrodes are equally spaced apart from each
other.
7. The array structure of nano materials of claim 5, wherein the
second conductive electrodes are equally spaced apart from each
other.
8. The array structure of nano materials of claim 5, wherein a
shape of the first conductive electrodes is any one of a square
pillar and a cylinder.
9. The array structure of nano materials of claim 5, wherein a
shape of the second conductive electrodes is any one of a square
pillar and a cylinder.
10. The array structure of nano materials of claim 5, wherein the
second conductive electrodes are taller than the first conductive
electrodes.
11. The array structure of nano materials of claim 5, wherein the
first and second nano material strands include any one of carbon
nanotubes and carbon nanowires.
12. The array structure of nano materials of claim 5, wherein the
first and second conductive electrodes form a shape L having a
corner, and wherein one of the second conductive electrodes is
located at the corner of the shape L.
13. The array structure of nano materials of claim 12, wherein the
first nano material strands protruding from the first conductive
electrode located at the corner of the shape L extend in a
transverse relationship with respect to the second conductive
electrodes.
14. An array structure of nano materials, comprising: a substrate;
a first array of first nano material strands extending along a
first direction and being directly/indirectly supported by the
substrate; a second array of second nano material strands extending
along a second direction and being directly/indirectly supported by
the substrate; at least one first conductive electrode electrically
contacting the first nano material strands and being mechanically
coupled with the substrate; and at least one second conductive
electrode electrically contacting the second nano material strands
and being mechanically coupled with the substrate, wherein the
first and second strands are disposed in a preset arrangement and
spaced apart from each other by at most several hundreds of
nanometers so that the first and second strands are configured to
interact with each other when disposed adjacent to a target.
15. The array structure of nano materials of claim 14, wherein the
first and second strands are disposed in a same elevation with
respect to the substrate.
16. The array structure of nano materials of claim 15, wherein the
first and second strands are disposed in different elevations with
respect to the substrate.
17. The array structure of nano materials of claim 16, wherein at
least some of the first strands and at least some of the second
strands are disposed in any one of a parallel, normal and
transverse relationship with respect to each other.
18. A method of preparing an array structure of nano materials,
comprising the steps of: providing a first layered structure having
multiple layers on a substrate, the first layered structure
including a layer having first nano material strands therein;
patterning the first layered structure to define first multiple
recesses such that end portions of the first nano material strands
and a part of the substrate in registration with the end portions
are exposed through the first multiple recesses; filling the first
multiple recesses with a conductive material to form an
intermediate structure; providing a second layered structure having
multiple layers on the intermediate structure, the second layered
structure including a layer having second nano material strands
therein; patterning the second layered structure to define second
multiple recesses such that end portions of the second nano
material strands and a part of the substrate in registration with
the end portions are exposed through the second multiple recesses;
and filling the second multiple recesses with a conductive
material.
19. The method according to claim 18, wherein the substrate
includes a transparent material.
20. The method according to claim 18, wherein the first nano
material strands are disposed in parallel and substantially equally
spaced apart from each other.
21. The method according to claim 18, wherein the second nano
material strands are disposed in parallel and substantially equally
spaced apart from each other.
22. The method according to claim 18, wherein the first and second
nano materials include any one of carbon nanotubes and carbon
nanowires.
23. The method according to claim 18, wherein the second nano
material strands are perpendicular to an extending direction of the
first nano material strands.
24. The method according to claim 18, further comprising the step
of trimming the first nano material strands to have a substantially
equal length.
25. The method according to claim 18, further comprising the step
of trimming the second nano material strands to have a
substantially equal length.
26. The method according to claim 18, wherein a shape of the first
multiple recesses is any one of a square pillar and a cylinder.
27. The method according to claim 18, wherein a shape of the second
multiple recesses is any one of a square pillar and a cylinder.
28. The method according to claim 18, wherein the first multiple
recesses and the second multiple recesses are arranged to form a
shape L having a corner, and wherein one of the second recesses is
located at the corner of the shape L.
29. The method according to claim 27, wherein one of the second
nano material strands extends in a transverse relationship with
respect to the first recesses, and wherein the remaining second
nano material strands extend in a transverse relationship with at
least a part of the first nano material strands.
30. The method according to claim 18, wherein the step of providing
the first layered structure comprises: depositing a first
photoresist layer on the substrate; patterning the first
photoresist layer to define first multiple grooves; filling the
first multiple grooves with nano materials so that the first nano
material strands match the respective grooves; and depositing a
second photoresist layer to cover the first photoresist layer
having the first nano material strands therein.
31. The method according to claim 30, wherein the step of providing
the second layered structure comprises: depositing a third
photoresist layer on the intermediate structure; patterning the
third photoresist layer to define second multiple grooves; filling
the second grooves with nano materials so that the second nano
material strands match the respective grooves; and depositing a
fourth photoresist layer to cover the third photoresist layer
having the second nano material strands therein.
32. The method according to claim 3 1, further comprising the step
of removing the first, second, third and fourth photoresist layers
after filling the second multiple recesses with the conductive
material.
33. The method according to claim 30, wherein a thickness of the
first nano material strands is less than a depth of the first
multiple grooves.
34. The method according to claim 31, wherein a thickness of the
second nano material strands is less than a depth of the second
multiple grooves.
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to an array
structure of nano materials.
BACKGROUND
[0002] One of the principal themes in the field of nanotechnology
is the development of nano materials on an atomic or molecular
scale (i.e., smaller than a micron). New or preeminent properties
of the nano materials are attributed to their nanoscale size.
Compared to macroscale materials, the materials reduced to
nanoscale display very different properties, which enable them to
be adapted for various applications. For example, an opaque
substance of macroscale may become a transparent substance of
nanoscale, a stable substance of macroscale may turn into a
combustible substance of nanoscale, a solid substance of macroscale
may be converted into a liquid substance of nanoscale at room
temperature, and an insulator of macroscale may become a conductor
of nanoscale. Due to such novel properties, the nano materials have
been widely applied in various fields.
[0003] However, despite their superior mechanical, chemical and
electrical properties, there have been certain drawbacks in using
the nano materials due to the difficulty of handling such small
materials in making a useful structure. In order to fully utilize
and apply the preeminent properties of the nano materials in
various fields, it is necessary to conceive various reliable nano
material cluster structures and suitable arrangement mechanisms for
positioning the same in a desired arrangement.
SUMMARY
[0004] The present disclosure provides a novel and innovative array
structure of nano materials. The array structure may comprise a
first set of conductive electrodes, a second set of conductive
electrodes and a plurality of first nano material strands
protruding from the first conductive electrodes. The first nano
material strands may be arranged in a coplanar relationship on a
first plane. The array structure may further comprise a plurality
of second nano material strands protruding from the second
conductive electrodes. The second nano material strands may be
arranged in a coplanar relationship on a second plane, which is
substantially parallel with the first plane. At least a portion of
the second nano material strands may extend in a parallel,
perpendicular or transverse relationship with respect to at least a
portion of the first nano material strands.
[0005] In one embodiment, the first conductive electrodes may be
equally spaced apart from each other. Alternatively, however, some
or all of the first electrodes may be unevenly spaced apart from
each other.
[0006] In another embodiment, the second conductive electrodes may
be equally spaced apart from each other. Alternatively, however,
some or all of the second electrodes may be unevenly spaced apart
from each other.
[0007] In yet another embodiment, the first electrodes may be
equally spaced apart from the second electrodes. Alternatively,
however, some or all of the first electrodes may be unevenly spaced
apart from the second electrodes.
[0008] In yet another embodiment, the first and/or second
conductive electrodes may generally have the shape of a square
pillar or cylinder.
[0009] In yet another embodiment, the first and second electrodes
may have the same shape. Alternatively, however, at least some of
the first and second electrodes may have different shapes.
[0010] In yet another embodiment, the second conductive electrodes
may be taller than the first conductive electrodes. Alternatively,
however, the second conductive electrodes may be shorter than the
first conductive electrodes.
[0011] In yet another embodiment, the first and second nano
material strands may include carbon nanotubes, carbon nanowires or
other elongated nano materials.
[0012] In yet another embodiment, the first and second conductive
electrodes may be arranged so as to form the shape L. Further, one
of the second conductive electrodes may be located at the corner of
the shape L.
[0013] In yet another embodiment, the first nano material strands
protruding from the first conductive electrode placed at the corner
of the shape L may extend in a transverse relationship with respect
to the second conductive electrodes.
[0014] The present disclosure provides another array structure of
nano materials. The array structure may comprise a substrate, a
first set of conductive electrodes disposed on the substrate, a
second set of conductive electrodes disposed on the substrate, and
a plurality of first and second nano material strands. The first
nano material strands may protrude from the first conductive
electrodes along at least a substantially similar first direction
and in a first elevation. Further, the second nano material strands
may protrude from the second conductive electrodes along at least a
substantially similar second direction and in a second elevation
from the substrate. The second elevation may differ from the first
elevation by at most several hundreds of nanometers. Accordingly,
the first and second nano materials may interact with each other
when disposed adjacent to a target.
[0015] The present disclosure provides yet another array structure
of nano materials. The array structure may comprise a substrate, a
first array of first nano material strands, a second array of
second nano material strands, at least one conductive electrode,
and at least one second conductive electrode. The first array of
first nano material strands may extend in a first direction and be
directly or indirectly supported by the substrate. The second array
of second nano material strands may extend in a second direction
and be directly or indirectly supported by the substrate. The first
conductive electrode may electrically contact the first nano
material strands and mechanically couple with the substrate.
Further, the second conductive electrode may electrically contact
the second nano material strands and mechanically couple with the
substrate. In addition, the first and second strands may be
disposed in a preset arrangement and spaced apart from each other
by at most several hundreds of nanometers. By doing so, the first
and second strands may interact with each other when disposed
adjacent to a target.
[0016] In one embodiment, the first and second strands may be
disposed in the same elevation with respect to the substrate.
[0017] In another embodiment, the first and second strands may be
disposed in different elevations with respect to the substrate.
[0018] In yet another embodiment, at least some of the first and
second strands may be disposed parallel, normal or transverse with
respect to each other.
[0019] The present disclosure further provides a novel method of
preparing an array structure of nano materials. Such a method may
comprise the step of providing a first layered structure having
multiple layers on a substrate. The first layered structure may
include a layer having first nano material strands therein. The
method of the present disclosure may also comprise the steps of
patterning the first layered structure to define first multiple
recesses such that end portions of the first nano material strands
and a part of the substrate in registration with the end portions
are exposed through said first multiple recesses, filling said
first multiple recesses with a conductive material to provide an
intermediate structure, and providing a second layered structure
having multiple layers on the intermediate structure. The second
layered structure may include a layer having second nano material
strands therein. The above method may further comprise the steps of
patterning the second layered structure to define second multiple
recesses such that end portions of the second nano material strands
and a part of the substrate in registration with the end portions
are exposed through said second multiple recesses, and filling said
second multiple recesses with a conductive material.
[0020] In one embodiment, the substrate may include transparent
materials.
[0021] In another embodiment, the first nano material strands may
be arranged in parallel and substantially equally spaced apart from
each other.
[0022] In yet another embodiment, the second nano material strands
may be arranged in parallel and substantially equally spaced apart
from each other.
[0023] In yet another embodiment, the first and second nano
material strands may include carbon nanotubes or carbon
nanowires.
[0024] In yet another embodiment, the second nano material strands
may be arranged so as to be perpendicular to an extending direction
of the first nano material strands.
[0025] In yet another embodiment, the method may further comprise
the step of trimming the first nano material strands so that such
strands have a substantially equal length.
[0026] In yet another embodiment, the method may further comprise
the step of trimming the second nano material strands so that such
strands have a substantially equal length.
[0027] In yet another embodiment, the first multiple recesses may
generally have the shape of a square pillar or cylinder.
[0028] In yet another embodiment, the second multiple recesses may
generally have the shape of a square pillar or cylinder.
[0029] In yet another embodiment, the first multiple recesses and
the second multiple recesses may be arranged so as to form the
shape L. Further, one of the second recesses may be located at the
corner of the shape L.
[0030] In yet another embodiment, one of the second nano material
strands may be arranged to extend in a transverse relationship with
the first recesses. The remaining second nano material strands may
be arranged to extend in a transverse relationship with at least a
part of the first nano material strands.
[0031] In yet another embodiment, the step of providing the first
layered structure may comprise the steps of depositing a first
photoresist layer on the substrate, patterning the first
photoresist layer to define first multiple grooves, filling the
first multiple grooves with nano materials so that the first nano
material strands match the respective grooves, and depositing a
second photoresist layer to cover the first photoresist layer
having the first nano material strands therein.
[0032] In yet another embodiment, the step of providing the second
layered structure may comprise the steps of depositing a third
photoresist layer on the intermediate structure, patterning the
third photoresist layer to define second multiple grooves, filling
the second grooves with nano materials so that the second nano
material strands match the respective grooves, and depositing a
fourth photoresist layer to cover the third photoresist layer
having the second nano material strands therein.
[0033] In yet another embodiment, the method of the present
disclosure may further comprise the step of removing the first,
second, third and fourth photoresist layers after filling the
second multiple recesses with the conductive material.
[0034] In yet another embodiment, the thickness of the first nano
material strands may be less than the depth of the first multiple
grooves.
[0035] In yet another embodiment, the thickness of the second nano
material strands may be less than the depth of the second multiple
grooves
[0036] This Summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the Detailed Description. The Summary is not intended to identify
key or essential features of the claimed subject matter, nor is it
intended to be used to limit the scope of the claimed subject
matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIGS. 1A to 1C show schematic diagrams of an array structure
of nano materials in accordance with one embodiment; and
[0038] FIGS. 2 to 14 collectively show a process of preparing an
array structure of nano materials in accordance with one
embodiment.
DETAILED DESCRIPTION
[0039] In the following detailed description, reference is made to
the accompanying drawings, which form a part hereof In the
drawings, similar symbols typically identify similar components,
unless context dictates otherwise. The illustrative embodiments
described in the detailed description, drawings, and claims are not
meant to be limiting. Other embodiments may be utilized, and other
changes may be made, without departing from the spirit or scope of
the subject matter presented here. It will be readily understood
that the components of the present disclosure, as generally
described herein, and illustrated in the Figures, may be arranged,
substituted, combined, and designed in a wide variety of different
configurations, all of which are explicitly contemplated and make
part of this disclosure.
[0040] FIGS. 1A to 1C show schematic diagrams of an array structure
of nano materials 100 in accordance with one embodiment. It should
be appreciated that the structure may include arrays of nano
materials in different elevations, wherein such arrays may extend
parallel to each other, cross each other or overlap each other at a
preset angle. For simplicity of illustration, the following figures
exemplify the structures wherein the arrays cross each other. It
should be understood, however, that each and every embodiment
disclosed hereinafter may also apply to the structures wherein the
arrays are parallel or transverse to each other.
[0041] Specifically, FIG. 1A shows an oblique view of the array
structure of nano materials 100 from an upper right side position.
Further, FIGS. 1B and 1C show longitudinal and lateral
cross-sectional views of the array structure of nano materials 100
along lines A-A' and B-B', respectively.
[0042] As shown in FIG. 1A, the array structure of nano materials
100 may include a substrate 2. The substrate 2 may have any
arbitrary shape. In this example, however, the substrate 2 has the
shape of a thin plate including relatively large top and bottom
opposing surfaces and two pairs of slim and long lateral surfaces.
The substrate 2 may be formed from materials selected in
consideration of features required for a specific application
field. For example, a transparent glass, indium tin oxide or other
types of transparent or translucent materials may be used to
provide the substrate 2 for allowing the resulting structure to be
used in a transparent device. In another example, an electrically
conductive, semiconductive or insulative material may be employed
in the substrate 2 to allow the resulting structure to be used for
an electrical device. In another example, a ferromagnetic,
paramagnetic or ferromagnetic material may be used to form the
substrate 2 to allow the resulting structure to be used for a
magnetic device.
[0043] The array structure of nano materials 100 may further
include a first set of conductive electrodes 8. Each conductive
electrode 8 may take the shape of a square pillar having top and
bottom surfaces. In another embodiment, the conductive electrodes 8
may take the shape of a cylinder. The conductive electrodes 8 may
be aligned along an edge 22 of the substrate 2. The longitudinal
edges of the top and bottom surfaces of the conductive electrodes 8
may be substantially parallel to the edge 22 of the substrate 2. As
shown in FIG. 1A, the conductive electrodes 8 may be equally spaced
apart in the longitudinal direction. However, the present
disclosure is not limited to such an arrangement. Each conductive
electrode 8 may also have two pairs of lateral surfaces disposed
between and in perpendicular to the top and bottom surfaces. The
lateral surface 82 of each conductive electrode 8, which is distant
from the edge 22, is referred to as an inward side surface 82 of
the conductive electrode 8. The bottom surface of each conductive
electrode 8 may be attached to the top surface of the substrate 2.
The conductive electrodes 8 may be made from one or more
electrically conductive materials such as, for example, but not
limited to, Ag, Cu, Al, etc.
[0044] The array structure of nano materials 100 may further
include a set of conductive electrodes 14. Each conductive
electrode 14 may form the shape of a square pillar including a pair
of top and bottom surfaces. In another embodiment, the conductive
electrodes 14 may take the shape of a cylinder. The conductive
electrodes 14 may be aligned with the same or another edge 24 of
the substrate 2 (the provided figure shows the latter embodiment).
The longitudinal edges of the top and bottom surfaces of the
conductive electrodes 14 may be substantially parallel to the edge
24 of the substrate 2. As shown in FIG. 1A, the conductive
electrodes 14 may be equally spaced apart from each other in the
lateral direction. However, the present disclosure is not limited
to such an arrangement. Each conductive electrode 14 may also have
two pairs of lateral surfaces disposed between and in perpendicular
to the top and bottom surfaces. The lateral surface 142 of each
conductive electrode 14, which is distant from the edge 24, is
referred to as an inward side surface 142 of the conductive
electrode 14. The bottom surface of each conductive electrode 14
may be attached to the top surface of the substrate 2. The
conductive electrodes 14 may be made from one or more electrically
conductive materials such as, for example, but not limited to, Ag,
Cu, Al, etc.
[0045] The array structure of nano materials 100 may further
include a first set of nano material strands 5 protruding from the
inward side surfaces 82 of the conductive electrodes 8. Each of the
nano material strands 5 may have the shape of an elongated tube or
rod. The first set of nano material strands 5 may form a coplanar
relationship with each other and be substantially parallel to the
substrate 2. The distance between the substrate 2 and the nano
material strands 5 is represented by h. The nano material strands 5
may be substantially parallel to each other and be further
substantially perpendicular to the conductive electrodes 8. The
length of the laterally extending portion of the first nano
material strands 5 may be relatively greater than its width or
thickness. Although the illustrated embodiment shows the nano
material strands 5 as being equally spaced apart, said strands 5
may also be unequally or irregularly spaced apart from each other.
In one embodiment, the nano material strands 5 may include, for
example, carbon nanotubes, carbon nanowires or other elongated nano
materials.
[0046] The array structure of nano materials 100 may further
include a second set of nano material strands 11 protruding from
the inward side surfaces 142 of the conductive electrodes 14. Each
of the nano material strands 11 may have the shape of a thin and
fine tape. The nano material strands 11 may form a coplanar
relationship and be substantially parallel to the substrate 2. As
shown in FIG. 1A, the nano material strands 11 protruding from the
inward side surfaces 142 of the conductive electrodes 14 may extend
in a transverse relationship with the first set of conductive
electrodes 8 or the nano material strands 5 protruding therefrom.
The distance between the substrate 2 and the nano material strands
11 is represented by H (greater than h). The nano material strands
11 may be substantially parallel to each other and extend in the
longitudinal direction perpendicular to the conductive electrodes
14. The length of the longitudinally extending portion of the
second nano material strands 11 may be relatively greater than its
width or thickness. Although the illustrated embodiment shows the
nano material strands 11 as being equally spaced apart, said
strands 11 may also be unequally or irregularly spaced apart from
each other. In one embodiment, the nano material strands 11 may
include, for example, carbon nanotubes or carbon nanowires.
[0047] As shown in FIG. 1A, the first and second sets of conductive
electrodes 8, 14 may be respectively disposed along the edges 22,
24 of the substrate 2, which are perpendicular to each other to
thereby form the shape "L." Further, as shown in FIGS. 1A and 1B,
the conductive electrodes 14 may be taller than the conductive
electrodes 8. In this embodiment, one of the second conductive
electrodes 14 may be located at the corner of the shape L. Thus,
the nano material strand 11 protruding from the conductive
electrode 14, which may be located at the corner of the shape L,
may form and extend in a transverse relationship with the
conductive electrodes 8 (not the nano material strands 5).
[0048] In this embodiment, the first set of conductive electrodes 8
may be perpendicular to the second set of conductive electrodes 14.
Further, as described above, one of the second conductive
electrodes 14 may be placed at the corner of the shape L. However,
the present disclosure is not limited to such an arrangement. In
another embodiment, the first and second sets of conductive
electrodes may form an acute or obtuse angle therebetween. Further,
in another embodiment, the conductive electrode may not be located
at the corner of the shape L. The conductive electrodes 8 and the
nano material strands 5 protruding therefrom may be electrically
isolated and separately controlled from the conductive electrodes
14 and the nano material strands 11 protruding therefrom. As set
forth herein, the first and second electrodes may be disposed in a
parallel, perpendicular or transverse arrangement. Depending on the
arrangement, the nano material strands protruding from the first
and second electrodes may also be disposed in a parallel,
perpendicular or transverse arrangement.
[0049] FIGS. 2 to 14 collectively show a process of preparing an
array structure of nano materials in accordance with one
embodiment.
[0050] As shown in FIG. 2, a substrate 2 may be provided. As
described above, the substrate 2 may be selected in consideration
of features required for a specific application field. For example,
to allow the resulting structure to be used in an optical device,
the substrate 2 may be transparent, translucent or opaque. In
another embodiment, the substrate 2 may be electrically conductive,
semi-conductive or insulative when the resulting structure is to be
used as an electronic device. Similarly, the substrate 2 may be
ferromagnetic, paramagnetic and the like when the resulting device
is to be used in a magnetic device.
[0051] As shown in FIG. 3, a first photoresist layer 3 may be
deposited on the substrate 2 to a preset thickness. The thickness
of the photoresist layer 3 may be selected by those skilled in the
art in consideration of the relationship between etching resistance
and resolution. The first photoresist layer 3 may have a resolution
sufficient enough to enable a subsequent nanoscale fine patterning.
Further, the first photoresist layer 3 may be fabricated from one
or more conventional photoresist materials.
[0052] Referring to FIG. 4, the first photoresist layer 3 may be
patterned by photolithography or other equivalent processes to
define one or more grooves 4 thereon. The length of each groove 4
may be greater than its width in the longitudinal direction. As
shown in FIG. 4, the grooves 4 may be arranged in parallel to each
other. Further, the grooves 4 may be substantially equally spaced
apart from each other. However, it should be noted that the present
disclosure is not limited to such an arrangement. According to one
embodiment, the grooves formed in the first photoresist layer 3 may
have different lengths or widths. Further, according to one
embodiment, the grooves formed in the first photoresist layer may
be unequally or irregularly spaced apart from each other.
[0053] In one embodiment, the first photoresist layer 3 may be
exposed to an ultraviolet light through a mask having a fine groove
pattern image. The exposed photoresist layer 3 may then be
developed to form the grooves 4 by using a chemical etchant, plasma
gas or other equivalent materials. Alternatively, the photoresist
layer 3 may be patterned by other similar processes such as using
lasers, ion beams and the like.
[0054] The depth of the grooves 4 may be equal to or less than the
thickness of the first photoresist layer 3. In one embodiment, the
depth of the grooves 4 may be as shallow as possible. In case of
using a chemical etching method, a selected etchant, selected
etching time, etc. may control the depth of the grooves 4. The
depth of the grooves 4 may also be controlled by varying an
intensity of the lasers or ion beams, a period of exposure or other
process variables associated therewith.
[0055] Thereafter, as shown in FIG. 5, a nano material may be
deposited into the grooves 4 to define nano material strands 5
matching the respective grooves 4. The nano material strands 5 may
include, for example, but are not limited to, carbon nanotubes,
carbon nanowires, other elongated nano materials, quantum dots and
the like.
[0056] In one embodiment, a suspension, an emulsion, a solution or
liquid mixture of nano materials (hereinafter, collectively
referred to as "the suspension of nano materials") may be poured on
top of the first photoresist layer 3. The suspension of nano
materials may migrate into the grooves 4 by gravity, diffusion or
other mechanical, electrical or magnetic forces, and define the
shapes and sizes matching those of the grooves 4.
[0057] In one embodiment, a gas jet device may be used to eject a
stream of gas so as to sweep the poured suspension of nano
materials from the first photoresist layer 3. In such a case, a
greater amount of nano materials may enter the grooves due to the
pressure of the ejected gas stream. In one embodiment, after
supplying the suspension of nano materials over the grooves to
allow at least some of the nano materials to enter the grooves, a
gas jet device may be applied on the suspension of nano materials
to cause the nano-materials, which are disposed outside the groove,
to further move into the grooves and be trapped therein.
Alternatively, centrifugal force may be used to allow greater
amounts of nano materials to be aligned with the grooves 4 and then
enter the same. When diffusing the nano materials into the grooves
on the substrate using the centrifugal force, the substrate may be
placed in a substantially circular fluid channel, which is filled
with a fluid medium containing the nano materials. The fluid medium
may be caused to be rotated within the fluid channel, wherein the
nano materials may then be diffused into the grooves on the
substrate. Further, in another embodiment, when the nano materials
respond to electric or magnetic fields, external electric or
magnetic fields may allow such materials to be aligned with and
attracted (or repelled) into the grooves 4.
[0058] As shown in FIG. 6, a second photoresist layer 6 may be
deposited onto the first photoresist layer 3 so as to entirely
cover the grooves 4 having the nano material strands 5 disposed
therein. It should be noted that the second photoresist layers 6
may be fabricated from the same materials as the first photoresist
layer 3. Alternatively, the second photoresist layer 6 may be
fabricated from different materials as long as it can be removed
together with the first photoresist layer in one patterning stage.
Since the process of depositing the second photoresist layer 6 is
similar to the process of depositing the first photoresist layer 3,
its detailed explanations are omitted herein.
[0059] Thereafter, as shown in FIG. 7, the first and second
photoresist layers 3, 6 may be patterned by photolithography or
other equivalent processes to define the same number of recesses 7
as the grooves 4 passing through the first and second photoresist
layers 3, 6. The recesses 7 may be aligned with the edge 22 of the
substrate 2. Moreover, the recesses 7 may be equally spaced apart
from each other, although they are not limited to such an
arrangement. Further, photolithography or other equivalent
processes may be performed so as to remove a desired portion of the
first photoresist layer 3 disposed under the second photoresist
layer 6 to a preset depth. In one embodiment, the first and second
photoresist layers 3, 6 may be patterned away to expose the
substrate 2 through the recesses 7. The first and second
photoresist layers 3, 6 may be removed to expose end portions of
the nano material strands 5 extending in the grooves 4 of the first
photoresist layer 3 through the recesses 7.
[0060] In one embodiment, the recesses 7 may be patterned, for
example, to have a square pillar shape or cylinder shape. Although
only three recesses 7 are depicted in FIG. 7, it should be noted
that there may be more or less than three recesses.
[0061] Thereafter, as shown in FIG. 8, a conductive material may be
filled into the recesses 7 to physically and electrically contact
and enclose the exposed end portions of the nano material strands 5
so as to provide conductive electrodes 8. As a result, the nano
material strands 5 may make electrical contact with the conductive
electrodes 8. In one embodiment, the conductive material may
include, for example, but is not limited to, Ag, Cu, Al, etc.
[0062] As shown in FIG. 9, a third photoresist layer 9 may be
deposited on top of the conductive electrodes 8 and the remaining
second photoresist layer 6. Further, the materials selected for the
third photoresist layer 3 and the detailed deposition process may
be similar to those of the first photoresist layer 3 in FIG. 3.
Alternatively, the third photoresist layer 9 may be fabricated from
different materials and a different deposition process may be
employed.
[0063] Referring to FIG. 10, the third photoresist layer 9 may be
patterned by photolithography or other equivalent processes to
define one or more grooves 10. The longitudinal length of each
groove 10 may be much greater than the width in the lateral
direction. The grooves 10 may form a transverse relationship with
the grooves 4 defined in the first photoresist layer 3. As shown in
FIG. 10, the grooves 10 may be substantially parallel to each
other. Further, the grooves 10 may be equally spaced apart from
adjacent ones. However, it should be noted that the present
disclosure is not limited to such an arrangement. According to one
embodiment, the grooves formed in the third photoresist layer 9 may
be unequally or irregularly spaced apart from each other. Further,
the patterning process for the third photoresist layer 6 may be
similar to the process of patterning the first photoresist layer 3.
Thus, detailed explanations regarding the patterning process are
omitted herein.
[0064] As shown in FIG. 11, the nano materials may then be
deposited into the grooves 10 to define nano material strands 11
matching the respective grooves 10. The nano material strands 11
may include, for example, but are not limited to, carbon nanotubes,
carbon nanowires, other elongated nano materials and the like. It
should be noted that the selected nano materials for the strands 11
may or may not be the same as the nano materials for the strands 5.
Further, the detailed process of forming the nano material strands
11 may be similar to that of the nano material strands 5. Thus,
detailed explanations thereof are omitted herein.
[0065] Thereafter, a fourth photoresist layer 12 may be deposited
onto the third photoresist layer 9 so as to entirely cover the
grooves 10 having the nano material strands 11 disposed therein.
The fourth photoresist layers 12 may be fabricated from the same
material as the third photoresist layer 9. Alternatively, the
fourth photoresist layer 12 may be made from different materials as
long as it can be removed together with the third photoresist layer
9 in one patterning stage. The process of depositing the fourth
photoresist layer 12 may be similar to the process of depositing
the third photoresist layer 9.
[0066] Thereafter, as shown in FIG. 13, the first, second, third
and fourth photoresist layers 3, 6, 9, 12 may be patterned by
photolithography or other equivalent processes to define the same
number of recesses 13 as the grooves 10 passing through all the
photoresist layers 3, 6 9, 12. As shown in FIG. 13, the recesses 13
may be arranged in a line near the edge 24 of the substrate 2. The
recesses 13 may be equally spaced apart from each other, although
they are not limited to such an arrangement. Further,
photolithography or other equivalent processes may be performed
sufficiently deep enough to remove a desired portion of the
photoresist layers 3, 6, 9, 12. In one embodiment, the photoresist
layers 3, 6, 9, 12 may be patterned away to expose the substrate 2
through the recesses 7. The photo resist layers 3, 6, 9, 12 may be
removed to expose end portions of the nano material strands 11
extending in the grooves 10 of the third photoresist layer 3
through the recesses 7.
[0067] In one embodiment, the recesses 13 may be patterned, for
example, to have a square pillar shape or cylinder shape. Although
only three recesses 13 are depicted in FIG. 13, it should be noted
that there may be more or less than three recesses.
[0068] Referring to FIG. 14, a conductive material may then be
filled into the recesses 13 to physically and electrically contact
and enclose the exposed end portions of the nano material strands
11 so as to provide conductive electrodes 14. Thus, the nano
material strands 11 may electrically contact the conductive
electrodes 14. In one embodiment, the conductive material may
include, for example, but is not limited to, Ag, Cu, Al, etc.
[0069] Thereafter, the remaining photoresist layers 3, 6, 9, 12 may
be completely removed by an appropriate etching process or
equivalents thereof As a result, as shown in FIG. 1, an array
structure 100 of nano materials may remain on the substrate 2
including the nano material strands 11 protruding from one of the
conductive electrodes 14 or the nano material strands 5 protruding
from the conductive electrodes 8.
[0070] In one embodiment, the nano material strands 5 and the nano
material strands 11 may be trimmed so as to have a substantially
identical length. For the trimming process, a conventional ion beam
milling process, which burns the end portions of the nano material
strands 5, 11 exceeding a preset length, may be selected. However,
it should be noted herein that other processes known in the art may
be used instead.
[0071] In the embodiment shown in FIGS. 1 to 14, the array
structure 100 may include two layers including the nano material
strands 5, 11, each of which has an end coupled to the respective
conductive electrode 8, 14. However, in another embodiment, the
array structure of nano materials may include three or more layers
including nano material strands connected to conductive electrodes
as long as each conductive electrode and nano material strand are
electrically isolated from others.
[0072] The series of steps (i.e., depositing and patterning a
photoresist layer to form grooves, filling the grooves with nano
material, depositing and patterning another photoresist layer to
form recesses, and filling the recesses with a conductive material)
may be repeated two or more times according to the number of nano
strand layers included in the array structure of nano
materials.
[0073] Further, it should be noted that any processing method,
which is well known to or can be newly developed by those skilled
in the art, may be selected for the above deposition, patterning
and lithography processes. It should be also noted that any
materials, which are well known to or can be newly developed by
those skilled in the art, may be selected as the nano materials or
conductive materials.
[0074] The parallel, crossed or transverse array structure of nano
materials may be used as electronic, magnetic or optical components
or as parts of more complicated electronic or optical devices.
Especially, the above nano material cluster structures may be
highly useful in the field of display. According to the present
disclosure, various array structures of nano materials may be
provided and used for various universal electronic, magnetic or
optical devices.
[0075] In light of the present disclosure, those skilled in the art
will appreciate that the methods described herein may be
implemented in hardware, software, firmware, middleware or
combinations thereof and utilized in systems, subsystems,
components or sub-components thereof For example, a method
implemented in software may include computer code to perform the
operations of the method. This computer code may be stored in a
machine-readable medium, such as a processor-readable medium or a
computer program product, or transmitted as a computer data signal
embodied in a carrier wave, or a signal modulated by a carrier,
over a transmission medium or communication link. The
machine-readable medium or processor-readable medium may include
any medium capable of storing or transferring information in a form
readable and executable by a machine (e.g., a processor, computer,
etc.).
[0076] From the foregoing, it will be appreciated that various
embodiments of the present disclosure have been described herein
for purposes of illustration, and that various modifications may be
made without departing from the scope and spirit of the present
disclosure. Accordingly, the various embodiments disclosed herein
are not intended to be limiting, with the true scope and spirit
being indicated by the following claims.
* * * * *